Gastric bypass (GBP) and laparoscopic adjustable banding (AGB) are common procedures that can result in significant weight loss and significantly improve type 2 diabetes in 40-80% of cases. The mechanism and time course of these changes have not been well studied and are poorly understood. The primary aim of this study is to investigate the potential weight-independent mechanisms of diabetes remission after GBP, by comparing GBP and AGB subjects after similar weight loss.